The present invention relates to a connector locking structure. More particularly, the present invention relates to a connector locking structure where the connector remains locked when pulled in the direction in which the connector was inserted into another connector. Even more particularly, the present invention relates to a connector locking structure which permits the unlocking of a connector only when the connector is twisted.
Referring to FIG. 16, a conventional connector 100 includes a plurality of terminals (not shown) retained in an insulating housing 101. Lock arms 103 are integrally formed with the insulating housing 101. A locking protuberance 104, at the leading end of the lock arm 103, projects toward the outside of the insulating housing 101. The lock arms 103 are elastically deformable sideward in the plane of the drawing sheet of FIG. 16.
Referring to FIG. 17, the locking protuberance 104 includes side surfaces 106 forming right angles with a tapered locking surface 108. A first flat surface 105, and a second flat surface 107 create planar surfaces parallel to each other. The tapered locking surface 108 is tilted relative to the first flat surface 105 and the second flat surface 107.
Referring now also to FIG. 16, the connector 110 mates with the connector 100. Connector 110 includes a plurality of terminals 112 retained in an insulating housing 111. The terminals 112 are brought into contact with their corresponding terminals of the connector 100 when the units are mated. First and second window holes 113 (only one of which is shown in the cross section) are included in opposed side surfaces of the insulating housing 111. A tapered locking surface 114, located at the edge of each of the window holes 113, tapers down toward thc open end of the connector 110 (i.e., the lower end of the window hole 113 in FIG. 16).
When the connector 100 and its mate connector 110 are fitted together, the lock arms 103 are elastically deformed toward the inside of the connector. When the locking protuberances 104 reach the window holes 113, the lock arms 103 return outwardly to their original positions under their own restoration forces. The locking protuberances 104 engage their respective window holes 113. In this mated condition, the terminals of the connector 100 are mechanically and electrically connected to their respective terminals of the connector 111. The tapered locking surfaces 108 of the locking protuberances 104 are resiliently urged into contact with their respective tapered locking surfaces 114 of the window holes 113, to maintain the mated condition.
This type of locking mechanism is an auxiliary system. When the connector 100 is pulled downward, the tapered locking surfaces 108 slide over their corresponding tapered locking surface 114. The locked state of connector 100 with its mated connector 110 is thus readily disengaged.
Referring to FIG. 18, another conventional connector 200 includes a plurality of terminals (not shown) retained in an insulating housing 201. Lock arms 203 are integrally formed with the insulating housing 201. A groove 204 longitudinally formed in the vicinity of the base of the lock arm 203, permits flexing of the lock arm 203 in the plane of the drawing sheet of FIG. 18. A locking protuberance 205 at the leading end of the lock arms 203 projects toward the outside of the insulating housing 201. An unlocking button 206, integrally with an intermediate portion of the lock arm 203, extends outward from the insulating housing 201 to an exposed position where it can be pressed by a user to release the locked condition.
Referring to FIG. 19, the locking protuberance 205 includes side surfaces 209 forming right angles with a vertical locking surface 207. A first flat surface 206, and a second flat surface 208 create planar surfaces parallel to each other. The vertical locking surface 207 is tilted relative to the first flat surface 206 and the second flat surface 208.
Returning to FIG. 18, a connector 210 mates with the connector 200. Connector 210 includes a plurality of terminals 212 in an insulating housing 211. The terminals 212 are brought into contact with their corresponding terminals of the connector 200. A window hole 213 is included the side surface of the insulating housing 211. A vertical locking surface 214, located at the edge of the window hole 213, faces the open end of the connector 210 (i.e., the lower end of the window hole 213 in FIG. 16). A right angle is formed between the vertical locking surface 214 and the direction in which the connector 210 is inserted into its mate connector 200.
When the connector 200 and its mate connector 210 fit together, the lock arms 203 are elastically deformed toward the inside of the connector. When the locking protuberance 205 reaches the window hole 213, the lock arms 203 return outwardly to their original positions under their own restoration forces. Each of the locking protuberances 204 engage with their respective window holes 213. The terminals of the connector 200 are electrically connected to their mate terminals of the connector 211. The vertical locking surface 207 of the locking protuberance 205 contacts the vertical locking surface 214 of the window hole 213.
To disengage the connector 200 from its mated connector 210, the unlocking buttons 206 are pressed to elastically deform the lock arms 203 toward the grooves 204. The locking protuberances 205 are disengaged from their respective window holes 213. The connector 200 is then disengaged from its mate 210 by pulling the connector 200 downward.
When a user wishes to disconnect the connectors, the conventional connector 100 of FIG. 16, is readily disconnected. Even when the user does not wish to disconnect the connectors, however, the connectors are readily disconnected with only a relatively small external force applied to the connectors.
Connector 200 prevents such unintended disconnection of the connector by providing a positive locking mechanism. The user must press the unlocking buttons 206 to disconnect the connectors. The operation of connector 200 is difficult when it is located in an area of limited accessibility. For example, disconnecting connector 200 from its mate connector 210 is very laborious when the connectors are located behind a device, or in a region of close clearances.
Furthermore, the lock arms 203 much be elastically deformed until the locking protuberances 205 are disengaged from their respective window holes 213. Some users may press the unlocking button 206 with more force than necessary, thereby damaging the locking arms 203. This is a particular problem when the connector itself is made compact in association with the recent trend toward miniaturization. In very small connectors, the lock arms 203 are formed to be slender and are even more susceptible to fracture.